Aerated confections are widespread. The inclusion of gas bubbles in a confection provides unique textural properties (mouthfeel) and reduces the density of the confection. This has the advantage of reducing the calorie content of the confection as well as reducing production costs since less confectionery material (e.g. chocolate) is required.
A chocolate bar containing a bubble-filled central portion encased within a solid outer layer is known. The central portion is produced by mixing liquid chocolate with a gas (e.g. carbon dioxide or nitrogen) under an elevated pressure, depositing the aerated chocolate into a mould cavity and cooling the chocolate. Micro-bubbles in the chocolate expand once the chocolate is returned to atmospheric pressure. Cooling serves to preserve the bubbles. Subsequently, the aerated central portion is coated with an outer layer of chocolate by enrobing.
Confections comprising a shell and a filling are also commonplace. The shell provides structural rigidity as well as protecting the filling and/or preventing leakage of the filling. The shell is therefore typically formed from solidified chocolate. On the other hand, the filling may or may not be solidified. It is also possible to omit the filling, i.e. produce a hollow confection.
Confectionery shells are typically produced by depositing shell material into a mould cavity, vibrating the mould, allowing an outer layer of the material to solidify, and inverting and vibrating the mould to remove excess material (the so-called “inversion method”). The first vibration step is performed at a precise frequency and amplitude in order to remove air bubbles contained in the shell material. This prevents air bubbles breaking the surface of the shell, which could spoil the appearance of the shell and allow a filling to leak out of the finished confection.
As well as the inability to produce aerated shells of satisfactory quality, the inversion method suffers from the disadvantage that the excess material must be collected and treated (e.g. re-tempering of chocolate) to avoid wastage. Also, the shell typically does not have a uniform thickness, especially when using a shell material having a relatively high viscosity. This imposes restrictions on the composition (e.g. fat content) of the material. The method is also burdensome in that the deposited material must be cooled for long enough that part of it solidifies to form the shell, but not so long that too much of the material solidifies.
It is an object of the present invention to provide a method for manufacturing a confectionery shell which does not suffer from the disadvantages of the known methods.